Currently, liquid crystal display devices are widely used in display units of electronic devices, and backlight modules are important units in liquid crystal display devices for providing necessary light sources and achieve the functions of liquid crystal panels. For liquid crystal panels, when assembling during manufacturing processes or before selling, functions of liquid crystal panels should be examined, and display functions of liquid crystal panels can be activated only after being assembled with backlight modules during most examinations; different manufactured liquid crystal panels have different sizes. Backlight module jigs used during examination are solely designed according to different sizes, i.e. a certain size of backlight module jig should be designed for each size of backlight modules, such that backlight module jigs do not involve versatility, need much resources and the cost is high.